x is the number of adults and y is the number of children.
x + y = 12
<span>14x + 10y = 140
lets multiply the first equation by -10 and then add it to the second equation:
-10x - 10y = -120
</span>14x + 10y = <span>140
</span>-----------------------
4x + 0 = 20
x = 20/4
x = 5
then substitute in the original equation:
x + y = <span>12
</span>5 + y = <span>12
</span>y = 12 - 5
y = 7
therefore there were 5 adults and 7 children
Answer:
Car 1 : 40 miles per gallon
Car 2: 25 miles per gallon
Step-by-step explanation:
family has two cars. During one particular week, the first car consumed 15 gallons of gas. The second car consumed 25 gallons of gas. The two cars Drove a combined total of 1475 miles and the sum of their fuel efficiency was 65 miles per gallon. What were the fuel efficiency of each of the cars that week
Given that :
Fuel efficiency , car 1 = x
Fuel efficiency , car 2 = y
x + y = 65 - - (1)
15x + 35y = 1475 - - - (2)
x = 65 - y
15(65-y) + 35y
975 - 15y + 35y = 1475
20y = 14875 - 975
20y = 500
y = 25
Put y = 25 in (1)
x + y = 65
x + 25 = 65
x = 65 - 25
x = 40
Answer:
work is attached and shown
Answer:
C
Step-by-step explanation:
My notes are in the picture.
it is a graph of the function given.
You would divide 27 by 12.
27 / 12 = 2.25
So, he used 2.25 pounds per sandwich.
